The stocks of Tesla and Nio have the following expected returns:

State of Economy	Probability of State of Economy	Nio's Return if State Occurs	Tesla's Return if State Occurs
Recession	50%	-12%	-15%
Normal	15%	8%	6%
Boom	35%	13%	16%

What is the standard deviation of the portfolio where 30% is Nio and 70% is Tesla? [10 points]